Takahisa Nasuno

Clinical features of spontaneous coronary artery dissection

BACKGROUND Spontaneous coronary artery dissection (SCAD) is an infrequent but increasingly recognized cause of acute coronary syndrome (ACS). Previous case reports demonstrated that this condition occurs in young females with a low atherosclerotic risk factor burden and may be associated with peripartum or postpartum status. The purpose of this study was to review patients with angiographically confirmed SCAD to provide additional insight into the diagnosis and treatment of this condition. METHODS AND RESULTS We screened medical records of all patients with ACS from March 2001 to November 2012. From these patients, we selected patients with SCAD based on coronary angiographic review. Of a total of 1159 ACS patients, 10 patients (0.86%) were diagnosed with SCAD. The mean age of these patients was 46 years, and 9 were female. ST-elevation myocardial infarction (STEMI) was observed in 9 patients and 5 patients had no coronary risk factors. One patient was treated conservatively with medication alone and 3 patients underwent thrombectomy. Balloon angioplasty was performed in 2 patients, and a bare metal stent was placed in one of these patients later. In the remaining 4 patients, bare metal stents were implanted emergently. Follow-up coronary angiography showed appropriate repair of SCAD in all 10 patients. CONCLUSIONS In our experience, the clinical features of SCAD appear to be similar to those reported previously. SCAD appears to be rare, but it should be considered in ACS patients, especially in younger females.

The late-phase inflammatory response after drug-eluting stent implantation

Recent advances in drug-eluting stent (DES) technology have succeeded in preventing restenosis. In addition to inhibiting smooth muscle cell proliferation, DES greatly inhibits the local inflammatory response in the acute phase after implantation, leading to prevention of restenosis. However, a unique issue in DES implantation is an impairment of reendothelialization, which may result in abnormal wound healing. Consequently, a late-phase inflammatory relapse could appear in the long term after DES implantation. In this study, we measured serum levels of inflammatory markers, including interleukin (IL)-6, IL-8, tumor necrosis factor-α, monocyte chemoattractant protein-1, matrix metalloproteinase-9, and myeloperoxidase, as well as high-sensitivity C-reactive protein at follow-up coronary angiography (mean 9 months) in 54 patients who received DES stenting who did not experience restenosis, and compared them with 51 patients receiving bare-metal stents (BMS) without restenosis. The level of IL-6 was over the measurement threshold (≥2.22 pg/ml) in 12 patients (21 %) in the DES group, but in only 2 patients (4 %) in the BMS group (P = 0.003). IL-8 was significantly higher in the DES group than in the BMS group (4.51 ± 2.40 vs 3.84 ± 1.34 pg/ml, P = 0.015). The levels of other biomarkers were similar between the two groups. DES showed an increase in inflammatory cytokines in the late phase after implantation in comparison with patients who received BMS, suggesting late-stage inflammation. Therefore, the wound-healing response after DES implantation might be different from that after BMS.

Which has the stronger impact on coronary artery disease, eicosapentaenoic acid or docosahexaenoic acid?

It has been suggested that n-3 polyunsaturated fatty acids, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), protect against cardiovascular diseases, and EPA/arachidonic acid (AA) and DHA/AA ratios in serum are potential risk markers for coronary artery disease (CAD). The purpose of this study was to clarify the clinical significance of the difference in the EPA/AA ratio and the DHA/AA ratio in patients with CAD. In 369 patients with confirmed or suspected CAD who underwent diagnostic coronary angiography, we measured serum levels of EPA, DHA and AA and calculated the EPA/AA and DHA/AA ratios. The EPA/AA ratio was significantly lower in patients with acute coronary syndrome (ACS) than in patients with chronic CAD or chest pain syndrome (0.27±0.19 vs. 0.44±0.20, respectively; P<0.01), whereas the DHA/AA ratio was similar in the two groups (0.78±0.27 vs. 0.79±0.37). Multiple logistic regression analyses using various biomarkers related to coronary risk discriminated ACS from other disease entities and demonstrated that the EPA/AA ratio (odds ratio: 0.0012, 95% confidence interval: 0.00–0.16, P<0.01) but not the DHA/AA ratio (odds ratio: 1.05, 95% confidence interval: 0.98–1.12) was a significant independent predictive factor. Our findings suggest that the EPA/AA ratio might be more closely associated with the pathophysiology of CAD, especially with that of ACS, than the DHA/AA ratio. Our findings suggest that interventions with EPA agents or supplemental EPA intake, compared with DHA agents or supplemental DHA, may confer greater benefit for plaque stabilization to prevent the onset of ACS in patients with CAD.

Mobilization of progenitor cells and assessment of vessel healing after second generation drug-eluting stenting by optical coherence tomography

Background Bone marrow-derived progenitor cells likely contribute to both endothelial- and smooth muscle cell-dependent healing responses in stent-injured vessel sites. This study aimed to assess mobilization of progenitor cells and vessel healing after zotarolimus-eluting (ZES) and everolimus-eluting (EES) stents. Methods and results In 63 patients undergoing coronary stent implantation, we measured circulating CD34 + CD133 + CD45low cells and serum levels of biomarkers relevant to stem cell mobilization. In 31 patients of them, we assessed vessel healing within the stented segment using optical coherence tomography (OCT) imaging. The CD34 + CD133 + CD45low cells increased 68 ± 59% 7 days after bare metal stent (BMS), 10 ± 53% after ZES (P < 0.01 vs BMS), 3 ± 49% after EES (P < 0.001 vs BMS), compared with baseline. Percent change in CD34 + CD133 + CD45low cells was positively correlated with that in stromal cell-derived factor (SDF)-1α (R = 0.29, P = 0.034). Percentage of uncovered struts was higher in the EES group (14.4 ± 17.3%), compared with the BMS (0.7 ± 1.3, P < 0.01) and ZES (0.4 ± 0.5, P < 0.01) groups. The change in CD34 + CD133 + CD45low cells showed positive correlation with OCT-quantified mean neointimal area (R = 0.48, P < 0.01). Finally, circulating mononuclear cells obtained from 5 healthy volunteers were isolated to determine the effect of sirolimus, zotarolimus and everolimus on vascular cell differentiation. The differentiation of mononuclear cells into endothelial-like cells was dose-dependently suppressed by sirolimus, zotarolimus, and everolimus. Conclusions Mobilization of progenitor cells was suppressed, and differentiation of mononuclear cells into endothelial-like cells was inhibited, in association with increased number of uncovered stent struts, even after second generation drug-eluting stenting. These data suggest that new approaches are necessary to enhance stent healing.

The different features of angiographic peri-stent contrast staining after implantation of sirolimus-eluting stents

If we had a case with angiographic peri‐stent contrast staining(PSS)s after the first‐generation sirolimus‐eluting stent, we need a further observation using coronary imaging modalities to evaluate the risk of very late stent thrombosis due to PSSs and to continue or to resume the dual antiplatelet therapy if necessary.

Percutaneous Coronary Intervention for Spontaneous Coronary Artery Dissectionunder Intravascular Ultrasound Guidance

Percutaneous Coronary Intervention for Spontaneous Coronary Artery Dissection under Intravascular Ultrasound Guidance A 77-year-old woman underwent percutaneous coronary intervention (PCI) for a spontaneous coronary artery dissection (SCAD) lesion in right coronary artery. A guide wire was advanced to the dissecting lesion, but it was inserted into false lumen. Therefore, we advanced an intravascular ultrasound (IVUS) catheter over the false lumen guide wire. The IVUS observation from the false lumen was useful for navigating the second guide wire into the true lumen. Finally, 38 mm everolimus-eluting stent was successfully placed in the dissecting lesion with fully coverage. The IVUS guidance such as in this case would be promising for the PCI in SCAD case.

Effective Cibenzoline Treatment in a Patient With Midventricular Obstruction After Transcatheter Aortic Valve Implantation

An 80-year-old woman with severe aortic stenosis was admitted to our hospital for transcatheter aortic valve implantation (TAVI). She had New York Heart Association functional class III congestive heart failure. Her comorbidities included multiple myeloma, idiopathic thrombocytopenic purpura treated with chronic steroids, hypertension, diabetes mellitus, and persistent atrial fibrillation. Echocardiography demonstrated a calcified tricuspid aortic valve with leaflet restriction consistent with severe aortic stenosis (Figure 1A; Movie I in the Data Supplement). The instantaneous peak velocity across the aortic valve on Doppler imaging was 5.0 m/s, and the mean pressure gradient was 53 mm Hg (Figure 1B). The aortic valve area calculated by using the continuity equation was 0.49 cm2. A concentric left ventricular (LV) hypertrophy was observed in the septum, measuring 13 mm, and in the posterior wall, measuring 14 mm. The LV cavity was small, with an LV internal dimension of 39 mm at end diastole. LV ejection fraction was 80%. Late peaking of the midcavitary LV pressure gradient of 25 mm Hg at rest was observed, without LV outflow tract obstruction and systolic anterior motion of the mitral valve leaflet (Figure 1C). Coronary angiography revealed no significant coronary artery stenosis. Given her severe aortic stenosis and heart failure symptoms with comorbidities of severe …